Pantograph-trolley.



S. B. STEWART, JR. PANTOGRAPH TROLLEY.

APPLICATION FILED SEPT. 10, 1908.

1,098, 1 33. I Patented May 26,1914.

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UNITED STATES PATENT @F Y SAMUEL B. STEWART, J 3., OF SCHENECTADY, NEW YORK, ASSIGNOR T0 GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

PANTOGRAPH-TROLLEY.

Specification of Letters Patent.

Application filed September oj eos.

Patented May 26, 1914. Serial No. 452,412.

To all whom it may concern:

Be it known that I, SAMUEL B. Srnwanr, Jr., a citizen of the United States, residing at Schenectady, county of Schenectady,

tate of New York, have invented certain new and useful Improvements in Pantograph-Trolleys, of which the following is a specification.

This invention relates to current-collecting devices for electric railway cars, and its object is to enable the traveling contact to respond more readily to irregularities in the trolley wire.

When a car is running at a speed of forty miles an hour, or more, the trolley is unable to follow accurately the vertical variations of the trolley Wire owing to the inertia of the somewrat cumbersome trolley structure which imposes a certain sluggishness or lag upon its movements. Even with the catenary method of suspension there are still some places where the wire is higher than at other places, and if the trolley jumps off it entails arcing, trouble and delay. My invention remedies these difliculties by providing a supplemental mounting for the contact proper, so that it can have a certain range of play independent of the trolley structure, whereby, owing to the comparative lightness of the traveling contact, it will more readily and quickly adapt itself to variations in the stationary conductor.

The invention is capable of development in many different designs, some of which are shown in the accompanying drawing, in which Figure l is a side elevation of a pantograph trolley embodying one form of my invention; Fig. 2 is a top plan view thereof, and Figs. 3 and 4: show modified modes of mounting the traveling contact.

High speed electric locomotives are nowadays usually provided with pantograph trolleys, and I have therefore illustrated the application of my invention to such a structure, comprising toggle-arms or frame 1, 52 carrying a transverse sliding collecting shoe or pan 3, or a rotating collector 8. The upper ends of the upper members '2 of the toggles can be variously connected. In Figs. 1 and 2 they are pivoted to a short rigid bridge-piece 4, and the pan is hinged to the upper ends of short diverging levers 5 whose lower ends are pivoted to the bridgepiece, preferably by the same pivots 6 as the arms 2. These pivots pass through slots in said levers so that said levers can slide thereon and thus separate or approach as may be necessary. These slots are preferably arranged lengthwise of the bent ends 7 of said levers. A tension spring 8 connects the lower ends of the levers and urges the pan upwardly. When the trolley is in running position in contact with a trolley Wire, the pan will be somewhat depressed from the position in which it is shown being forced down until the tension of the spring 8 balances the upward thrust of the regular trol- Icy-lifting springs (not shown). The pan will thus float in an intermediate position with the pivots 6 about midway of the slots. Any sudden depression or elevation of the pan, due to a variation in the trolley wire, will be taken care of by the spring 8 which will yield quickly to a depression and contract quickly to follow up an elevation of the trolley wire. The lightness of the pan and its supporting levers, as compared with the weight of the entire trolley structure, enables it to follow the wire very closely, and to a large extent independently of the movements of the somewhat cumbersome and slow-moving pantograph structure.

In lieu of the bridge-piece t, I may cross the upper ends of the arms 2 and pivot them together at 9, as shown in Fig. 3. In other respects, the device shown in this figure is the same as that in Fig. 1, except that a roller 3 is substituted for the sliding pan 3.

Fig. 4 shows the pan or equivalent traveling contact mounted on flat arched springs 10 instead of on pivoted levers. The arch 10 has horizontal ends supported in any suitable manner by the upper arms 2, preferably on plates 11 pivoted to the arms, and either one or both ends of the arch has a horizontal slot 12 engaging with a headed pin 13 inserted in the plate. This permits the arch to flatten down when pressure is brought to bear upon the traveling contact, said end sliding back and forth on the plates as the contact floats up and down in following the variations of the trolley wire. The tension of the spring arch of course increases as it is flattened down, so that it will quickly assume a position corresponding with the upward thrust of the pantograph springs. By means of these or equivalent supplemental mountings for the trolley pan, a

trolley is produced which will closely follow the undulations of the trolley-wire at modern railway speeds.

WVhat I claim as new and desire to secure by Letters Patent of the United States, is,

1. The combination with a pantograph trolley, of a transversely extending current collector, pairs of levers pivoted to the upper arms and supporting the current collector, and resilient means acting upon said levers for urging said collector directly upward.

2. The combination with a pantograph trolley, of levers pivoted to the traveling contact and to the upper arms of the trolley, and resilient connections attached to the lower ends of said levers.

3. The combination with a pantograph trolley, of a pair of levers pivoted to the traveling contact and having slots engaging pivots on the upper arms of the trolley, and a spring connecting said levers.

4. The combination with a pantograph trolley, of a bridge-piece ivoted to the upper arms thereof, a pair 0 levers pivoted to the traveling contact and having bent ends containing slots engaging pivots on said bridge-piece, and a tension spring connecting the ends of said levers.

In witness whereof, I have hereunto set my hand this 9th day of September, 1908.

SAMUEL B. STLEWART, JR.

WVitnesses BENJAMIN B. HULL, MAY \NHITTAKER.

Copies of this patent may be obtained for five cents each, by addressing the Gommissioner of 'Eatents, Washington, D. C. 

